To be frank, I was surprised by the writing of the show and didn't expect that I'd like the story line this much. The focus on the characters' internal developments and how they stayed the same/differ from their past selves were a joy to watch. I love the dynamic between the teenager Ha-ni and adult Ha-ni, learning about the moments that shaped who the adult Ha-ni's life choices. I also appreciated that the romance line going on is a sub-plot and that there are actual progress of the two falling for each other. The only major issue I have regarding the storyline is the time skip at the end, the way the ending went doesn't makes sense based on how traveling generally work (if you change something in the past, the future will change). I suppose it's ok for having a very nicely tied up ending.